Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 3841: SNe; Her X-1; PG 1115+080

The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).

Read IAUC 3840 SEARCH Read IAUC 3842
IAUC number 

                                                  Circular No. 3841
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM     Telephone 617-864-5758


SUPERNOVAE
     P. S. Pellegrini, Observatorio Astrofisico Brasileiro, Itajuba,
reports the discovery by M. Nunes, L. N. da Costa, D. Latham
and himself of a possible supernova 7" east and 5" south of the
nucleus of NGC 5746 (R.A. = 14h42m3, Decl. = +2deg10', equinox 1950.0).
The object was estimated at mv ~ 13 on July 11.  Features resembling
those of a supernova were noted on an intensified reticon
spectrogram obtained at the Cassegrain focus of the 1.6-m telescope.

     Visual magnitude estimates of the supernova in NGC 5236: July
6.5, 11.8 (R. Evans, Maclean, N.S.W.); 7.4, 11.6 (Evans); 8.57,
11.5 (Evans); 10.2, 11.2 (T. Langhans, San Bruno, CA; communicated
by J. Mattei); 11.2, 11.2 (Langhans); 12.2, 11.2 (Langhans).


HERCULES X-1
     The EXOSAT Observatory Team reports: "Four EXOSAT observations
of Her X-1 = HZ Her during June 28.13-28.33, 30.57-30.80,
July 8.67-9.55 and 17.44-17.53 UT did not detect a 35-day on-state
as predicted by the turn-on times listed by Crosa and Boynton
(1980, Ap.J. 235, 999).  AAVSO monitoring (provided by J. Mattei)
shows that the optical modulation associated with x-ray heating of
the primary was present during the ESOSAT observations.  This
suggests that the phase of the 35-day cycle has changed dramatically
and that Her X-1 may be entering an extended low state."


PG 1115+080
     C. Vanderriest, G. Wlerick and P. Felenbok, Observatoire de
Meudon, have observed with the Canada-France-Hawaii Telescope an
important variation in the V flux of the components of the
gravitationally-lensed object PG 1115+080 (Weymann et al. 1980, Nature
285, 641: R.A. = 11h15m41s5, Decl. = +8deg02'24" , equinox 1950.0),
namely:

                Total      A        B        C      B/A      C/A

1981 Apr. 30    16.04    16.40    18.35    17.99    0.166    0.231
              +/-0.04  +/-0.04  +/-0.08  +/-0.06 +/-0.020 +/-0.020
1983 Mar.  7    16.62    16.91    19.24    18.71    0.117    0.190
              +/-0.03  +/-0.03  +/-0.06  +/-0.05 +/-0.020 +/-0.020

For the 1981 observations the receptor was the valve electronographic
camera.  For 1983 it was the wide-field electronographic
camera.  The photometry is based on a sequence of four stars.


1983 July 21                   (3841)              Brian G. Marsden

Read IAUC 3840 SEARCH Read IAUC 3842

Our Web policy. Index to the CBAT/MPC/ICQ pages.

Valid HTML 4.01!